Chromatography is a widely used analytical technique for the chemical analysis and separation of molecules. Chromatography involves the separation of one or more analyte species from other matrix component present in a sample. A stationary phase of a chromatography column is typically selected so that there is an interaction with the analyte. Such interactions can be ionic, hydrophilic, hydrophobic, or combinations thereof. For example, the stationary phase can be derivatized with ionic moieties that ideally will bind to ionic analytes and matrix components with varying levels of affinity. A mobile phase is percolated through the stationary phase and competes with the analyte and matrix components for binding to the ionic moieties. The mobile phase is a term used to describe a liquid solvent or buffer solution that is pumped into a chromatography column inlet. During this competition, the analyte and matrix components will elute off of the stationary phase as a function of time and then be subsequently detected at a detector. Examples of some typical detectors are a conductivity detector, a UV-VIS spectrophotometer, and a mass spectrometer. Over the years, chromatography has developed into a powerful analytical tool that is useful for creating a healthier, cleaner, and safer environment where complex sample mixtures can be separated and analyzed for various industries such as water quality, environmental monitoring, food analysis, pharmaceutical, and biotechnology.
Applicant believes that there is a need for improved ion exchange chromatographic resins where the observed retention times can be tailored to a specific sample analysis such as, for example, cations of alkali metals, alkaline earth metals, and various amine compounds in water. One strategy for tailoring retention times is to vary the concentration of the ion exchange groups on the resin. In addition, Applicant also believes that there is a need for a platform chemistry that allows for reducing the ion exchange group concentration on the resin while retaining the ability to separate samples with relatively high efficiency.